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EARTHQUAKES, NEUTRINOS AND THIS THING CALLED SCIENCE

What links the trial of six scientists in the Italian town of L’Aquila, accused of failing to predict an earthquake, with the neutrinos that may have travelled faster than the speed of light? The answer is that these two very different stories that have hit the headlines in recent weeks both throw light upon changing perceptions of science – and upon how the social role of science is changing too.

In April 2009, a devastating earthquake struck the town of L’Aquila, killing 308 people and leaving more than 65,000 homeless. A year later six seismologists and a government official were charged with manslaughter for providing the authorities with ‘incomplete, imprecise and contradictory information about the nature, causes and future developments of the seismic hazards.’

The facts of the case are complex. In the early months of 2009, increasing seismic activity in l’Aquila had created a sense of panic. In response, Italy’s Department of Civil Protection (DCP) convened a meeting of its Major Hazards Committee in the town at the end of March. ‘There is no reason’, that meeting concluded, ‘to say that a sequence of small-magnitude events can be considered a predictor of a strong event.’ But neither could the possibility of a major quake be excluded. Enzo Boschi, the then-president of Italy’s National Institute of Geophysics and Vulcanology, a member of the Major Hazards Committee and now a defendant in the case, pointed out that while ‘It is unlikely’ that a major earthquake ‘could occur in the short term’, nevertheless ‘the possibility cannot be totally excluded.’ At a later press conference, DCP vice-president Bernardo de Bernardinis, neither a seismologist nor a member of the Major Hazards Committee, made a somewhat different claim. ‘The scientific community tells us there is no danger’, he said, ‘because there is an ongoing discharge of energy. The situation looks favourable.’ A week later L’Aquila was hit by a 6.3 magnitude quake.

For some, the L’Aquila affair is a matter of miscommunication. The claim of the Major Hazards Committee that ‘a sequence of small-magnitude events’ could not predict a major quake but could not rule it out either was scientifically robust. Bernardinis’ comment that there was ‘no danger’ because of ‘an ongoing discharge of energy’ was scientific nonsense.

The issue, however, runs far deeper than a question of whether a layman mangled up his understanding of seismology. What the L’Aquila case reveals is the degree to which we now lean upon science for certainty and reassurance, but also turn upon it when it is unable to deliver it. The people of L’Aquila wanted their anxieties assuaged; Bernardinis seemed to deliver. But having looked to science for comfort and certainty, when disaster struck, and false reassurance was ripped away, there was a deep sense of betrayal. Science became the scapegoat for people’s sense of rage and grief.

We live in an age of tremendous confusion and dislocation – moral, political and social – and this has shaped public attitudes to science. On the one hand, the sense of a world out of control has created a craving for certainty. On the other, as people have become disenchanted with politics, so science has acquired a new authority as a means through which to find that certainty. ‘Science tells us…’ has become a common refrain in political debates, from whether young children should be put in nurseries to how to combat climate change. It is a refrain that allows politicians to draw upon the authority of science to shore up their own discredited authority. The consequence, however, is that the authority of science itself is becoming eroded.

Mike Hulme, one of Britain’s leading climate scientists, believes that claims of science ‘proving’ the need for particular policy measures – such as, for instance, an 80% cut in carbon emissions – are dangerous. This is not because he disputes, say, the reality of man-made global warming or the need for emission cuts, but because ‘When science is invoked to support such dogmatic assertions, the essential character of scientific knowledge is lost – knowledge that results from open, always questioning, enquiry that, at best, can offer varying degrees of confidence about how the world is, or may, become.’ Inevitably, as in L’Aquila, confidence in science itself becomes shaken.

The demand for certainty from science can be seen also in the other science story that has hit the headlines in recent weeks: the news that a group working at the CERN laboratory in Geneva may have discovered that neutrinos can travel faster than light, a story that has caused a sensation, both within the physics community and among those who wouldn’t know the difference between a neutrino and a nebula. If true, then some of the most fundamental assumptions of modern physics may be thrown into question.

The key phrase, of course, is ‘if true’. Many, probably most, physicists have been skeptical about the results. The CERN group have replicated their results some 16,000 times. Yet most physicists still believe that some deep, so far unidentified, error is responsible. Even the scientists who conducted the experiment remain cautious. ‘We are very much astonished by this result’, project co-ordinator Antonio Ereditato observed, ‘but a result is never a discovery until other people confirm it.’ This is how science, at its best, should work: leavened with a healthy dose of skepticism, open to scrutiny from peers, results not accepted unless independently replicated.

Just suppose, however, that it turns out to be true that there are particles that can travel faster than light. The fact that this would mean rethinking some of the most fundamental assumptions of modern physics, including notions of causality and objectivity, has created considerable excitement. It has also generated anxieties. The news, one BBC reporter suggested, could lead to ‘the sense of certainty that we think science brings to us being taken away’. ‘Isn’t it rather frightening’, she asked Maggie Aderin-Pocock, a physicist, ‘because everything you’ve learnt so far could be undermined?’

To ask such a question is, however, to think of science as a form of faith, as something fixed and incontrovertible. Scientific knowledge is always provisional, always open to challenge and to change. Not in the sense that ‘anything goes’, or that scientific theories are no more than ‘stories’, but in the sense that the whole point of science is continually to improve our understanding of the world. And that means keeping an open mind and being prepared to admit that we are wrong or incomplete. I am as certain as can be that humans are evolved beings, as is all life on Earth. But if someone were to provide incontrovertible proof that evolution was false, then I would have to rethink my certainties. Most physicists remain as certain as they can be that nothing can travel faster than light. But were the CERN results to be verified, then they, too, may have to change their minds.

What links the physical earthquake in L’Aquila caused by seismic events to the metaphoric earthquake in CERN caused possibly by faster-than-light neutrinos is the changing perception of science within society, and the growing confusion of scientific claims and dogmatic certainty. Such confusion, more than any possible challenge to the fundamental assumptions of modern physics, is what should truly concern us.

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3 comments

Seems to me the problem is part and parcel of what it means to be a human being… we are capable of rational thought, of projecting ourselves in time from a past that once was to a future not yet realized, and we can of course even contemplate our own mortality… our prefrontal cortex gives us the capacity (or burden?) of being able to live so much of our lives focused on the future… but the future is seldom predictable and we are left fearful and anxious. We want answers to our many questions. It seems to me that our classical religions used to fill that role, but they are hard to reconcile against the power of rational thought and empirical science. So now we turn to science… (could we not turn equally to rational thought?)… but if we are not careful, it becomes its own ideology… this form of science is indeed dangerous, and I agree, it will probably hurt our view of it in the long run.

The OPERA result was not replicated 16000 times. The group detected 16000 neutrinos of the 10^20 launched from CERN. They matched the time profile of these 16000 events to the long bunchs created at CERN and found the best statisical match with a lag 60 nanoseconds shorter than the speed of light through vacuum suggests is appropriate. OTOH, the neutrinos were going through the earth and gravity affects them. Further, starting from a bunch profile 5 microseconds long and concluding something statistically at 1% of this length, ostensibly with an error of 0.1% of this length, is not something most physicists sign up for.

Fermilab and KEK will attempt to duplicate the experiment with shorter bunches, hence reduced need for statistical timing conclusions. The bunch length at CERN is set by the needs of LHC injection and CERN may not be able to shorten it in between fills of LHC and still generate enough neutrinos for OPERA to detect. Recall that only one in 10^16 neutrinos is detected, so CERN would have to generate a thousand times as many 5 ns pulses to get the same response at OPERA.